April 3, 2006

Liver cancer cell growth prevented by omega-3 fatty acids

The results of two studies presented on April 3, 2006 at the American Association for Cancer Research's annual meeting revealed that the omega-3 fatty acids eicosapenaenoic acid (EPA) and docosahexaenoic acid (DHA) inhibit the growth of liver cancer cells in culture.

Tong Wu, MD, PhD, who is a member of the division of transplantation pathology at the University of Pittsburgh School of Medicine, and whose laboratory was used to conduct the research explained, "It has been known for some time that omega-3 fatty acids can inhibit certain cancer cells. So, we were interested in determining whether these substances could inhibit liver cancer cells. If so, we also wanted to know by what mechanism this inhibition occurs."

The research team examined the effect of DHA and EPA and the omega-6 fatty acid arachidonic acid in human hepatoceullar cancer cells, a common type of liver cancer. After treating the cells for 12 to 24 hours, they found an inhibition of cell growth dose-dependently associated with EPA and DHA, while arachidonic acid failed to have an effect. They believe that the effect observed in this study was due to apoptosis, or programmed self-destruction, of the cancer cells. In addition, DHA and EPA indirectly reduced levels of the protein beta-catenin, which, when elevated, has been linked to the development of some tumors.

A second experiment looked at the effect of omega-3 and omega-6 fatty acids in cholangiocarcinoma cells, which is an agressive form of liver cancer, and discovered a similar ability of omega-3 fatty acids to inhibit cell growth and lower beta-catenin.

"Our finding that omega-3 fatty acids can decrease levels of beta-catenin is further evidence that these compounds have the ability to interact on several points of pathways involved in tumor progression," Dr Wu concluded.